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' @uitrit tatrs @anni @frn JAMES D. DRIGGS, 0F NEW'BEDFORD,MASSACHUSETTS, ASSIGNOR TO HIMSELF AND EDWARD MERRlLL, OF SAME PLAGE.

Letters Patent No. 69,644, dated October 8, 1867.

fro ALL WHoM 1T MAY CONCERN- De it known rthat I, JAMES-D. DRIGGS, ofNew Bedford, in the county of Bristol, in the State of MassaA chusetts,have invented a. new and improved Mode of Starting a-Bolt, Rod, or Pipeinto a Die for the purpose of cutting a thread thereon; and I do herebydeclare that the following is a full and exact description thereof,reference being had to. the accompanying drawings, and to the letters ofreference marked thereon.

My invention consists in a frame attached to the die-plate, in which isscrewed a cylinderhaving a screw cut upon itsouter surface, containingthe same number of threads to the' inch asithe die, and with a bore justlarge enough to admit the bolt, or-other article, in which cylinder, theholt, rod, or pipe to be cut is secured by a set-screw. i L

Figure 1 is a longitudinal section of a screw-plate with my inventionattached to it.

Figure 2 is a view of the under side of a die-plate, having the frame,attached thereto, the cylinder being removed.

Figure 3 is a view of the cylinder. Fig. 1. Al is the die-plate; B1,-theframe for reception of the cylinder; C1, cylinder, in which the bolt issecured; D, set-screw in cylinder to secure bolt; El, dies.

Fig. 2. A.2 dieplate, B2 tfame, Ez dies.

Fig. 3. C3 cylinder, D3 set-screw..

Operation.'

The within device being constructed as herein shown, and-aixed asalso'shown, its operation may be noted. The cylinder is turned out inframe, as shown in fig. 1, and a bolt, rod, or pipe, on which it isdesired to cut a "thread, being secured in a v'ise, the cylinder isslipped on to the bolt till the end of the latter strikes the dies,

when it may be secured by the set-screw. Now, by turning the plate theframe is screwed on to the cylinder, forcing the dies on to the bolt.After a few turns the set-screw may be loosened, permitting the cylinderto revolve on the bolt, in which condition it will act as a guide, anda. thread may bc cut as far as desired. By this device all the troubleattending the starting a thread on a bolt, etc., is obviated,` and thebolt, etc., will not need pointing, thereby saving much time. Y

' C'laz'm.

What I claim' as my inventlon, and desire to secure by Letters Patent,is

The'frame B`and cylinder C, with set-screw D, applied to a die-plate,substantially as and for the purpose hereinspecified.

JAMES D. DRIGGS.

Witnesses:

JNO. DAVIS, 'TIL E. M. WHITE.

